My experiments this week were largely what I would call thought experiments. I had two main ones and they both apply to the idea of me producing some sort of DIY speaker system. Ideally, this speaker would allow people to replicate it, and while doing so learn about main design aspects that alter the performance of them.

This system would have some aspect of modularity within its design. My first experiment was playing with what the idea of modular would mean to a speaker and what I could achieve with a modular design.

Modularity in Speakers

What will I achieve with modularity?

Modularity in this case would provide the user (and myself) with greater understanding of how physical changes can shape the sound of a speaker. The goal of a modular speaker in this context would be education through modularity. The modular form would allow the user to relatively quickly augment the form of the speaker and listen to the results those changes have made. Ideally, the modularity would speed up the time needed between listening to blind A & B tests between audio.

Forms of modularity

  1. Modular form all-in-one - This form would be a single pair of speakers which have the ability to have their forms rapidly altered. The interior volumes expandable and contractable, the front baffle can increase in surface area, ports on the body can be easily plugged up, panels of the body can be added or removed, and drivers able to be swapped in and out rapidly. Internal structures could also be changed creating new pathways of air flow.
  2. Common body, multiple variations - This entails making a variety of test speakers which all share a common rough blueprint that can be altered easily and obviously. The changes between speakers would be the same as the ones listed in the above option, but would likely require the construction of a new speaker. The modularity in this case exists within the planning of the speaker, aiding the fabricator in planning them out rather than serving as an all-in-one tool.
  3. Circuitry Modularity The proposed speakers would be passive speakers, meaning they require some version of a crossover frequency as a means of filtering the correct frequencies of audio from the amplification line. These circuits would need to change as specific changes to the speaker form occur. This could take a few different forms:
    1. An active crossover - the simplest version of this, something off the shelf that can be adjusted on the fly. It would require to be plugged into an outlet.
    2. A few different crossovers that you can mechanically switch between or have some swappable construction. This version would limit the changes you can make depending on how many independent circuits you are willing to make.

Materials for Construction of a pair of DIY Speakers

Selecting the materials of a speaker, specifically in the context of DIY are of the utmost importance due to material availability and ease of fabrication becoming huge selling points. Due to these points, I would restrict myself to the materials listed below for a project like this.

MDF

Typically, speakers are made from composite wood boards, usually MDF. This is mainly because they are relatively sonically dead, there is not a lot of reverberations because of how dense the material is. MDF is a great option for DIY speakers as well, because it is readily available and you need basic woodshop tools to cut it.

Plywood